APPLICANT'S ABSTRACT: This research will test whether a drug of abuse, cocaine, can influence the ability of an animal to respond to a significant environmental stimulus. We and others have shown that female house mice respond to a pheromone in urine of adult males by attaining puberty significantly earlier than control animals. Our preliminary data suggest this pheromonal stimulus can be blocked by the treatment of cocaine. We propose to confirm this finding and explore whether reception of the pheromone by juvenile females can be attenuated by the administration of cocaine and whether the production of the pheromone by the adult male is altered. The reproductive performance of cocaine-treated females and their daughters will be examined to determine if reproductive competence is compromised by cocaine in the mother and her offspring. Results from these experiments may reveal that an animal can be isolated from elements of its social environment by cocaine. If so, this could have a strong effect on the animal's reproductive fitness since the social environment has a powerful influence on reproductive events. By implication, it may also suggest that cocaine may induce a reduction in responsiveness of humans to significant social stimuli. We anticipate that the results of the research proposed here will lead to the preparation of a multi-year research grant proposal.